At the beginning of combat on your turn, create a 2/1 blue Phyrexian Myr artifact creature token. Then you may choose a token you control. If you do, each other token you control becomes a copy of that token.
Brudiclad turns a wide-but-weak board of tokens into an army of identical bombs each combat. You generate cheap tokens, copy options (powerful creature tokens or dangerous tokens like Dragons/Demons), then at combat use Brudiclad to transform every token into copies of your best one and swing for lethal with haste. The deck mulligans toward ramp into Brudiclad on turn 5-6 and a token to copy.
Explosive, instant turnaround: an unimpressive board becomes lethal in a single combat
Built-in haste means copied tokens attack the turn they're made
Flexible payload — copy a flier, a Blightsteel Colossus token, or even an opponent's token
Free token every turn keeps the engine fueled even after board wipes
Brudiclad is a 6-mana glass cannon that telegraphs your plan; removal or a fog blanks the turn
Heavily commander-dependent — without him the deck does little
Board wipes and instant-speed spot removal during combat are backbreaking
Needs a quality token to copy or the ability does nothing exciting
Generates extra copies of key creatures to feed Brudiclad and enables combo lines.
Add fast mana (Sol Ring, Dockside, Mana Crypt) to land Brudiclad earlier and free token generators like Hangarback Walker, Myr Battlesphere, or Ophiomancer to always have copy fodder. Include protection (Heroic Intervention, Lightning Greaves) so he survives to combat, and tutors plus copy enablers (Saheeli, Kiki-Jiki) to assemble explosive turns more reliably. Tighten the mana base and trim slow tokens that don't translate into a lethal copy target.